Analyzing Ancillary Impacts of Solar Photovoltaic to Natural Gas Electricity Generation

Abstract

The U.S. economy is heavily dependent on nonrenewable fossil fuels for its electricity. It is widely known that the supply of these nonrenewable resources is large yet limited. Renewable sources of electricity are currently needed to meet incremental demand in the short term and will play an increasingly important role as the United States continues to create an infrastructure that does not rely exclusively on fossil fuels. Solar photovoltaic (PV) provides the ability to generate clean energy while using existing electrical transmission infrastructure, or even bypassing it entirely. In order to gain a more robust understanding of the implications of electricity generation, this study compares PV solar power to conventional fossil fuel generated electricity – primarily natural gas – with respect to five ancillary impacts beyond energy generated and cost of generation. Solar PV has an advantage over other renewable technologies because it can be deployed at a small or a large scale, making distributed generation and utility-scale installations equally feasible. In addition, the ubiquity of sunlight makes solar PV feasible in regions and sites with varying degrees of sunlight exposure. The purpose of this study is to examine ancillary impacts of solar PV relative to natural gas that are relevant to many stakeholders. After speaking with industry experts and leaders at various levels of government, the following five ancillary impacts emerged as the most significant, quantifiable, and relevant: • Water use • CO2 emissions • NOX emissions • Health benefits of avoided emissions • Job creation and economic benefits to a community or region The ancillary impacts are important in examining electrical generation capacity additions at a community or regional level in order to gain a more holistic understanding of solar PV. This study uses a natural gas combined-cycle (NGCC) as a baseline for comparison with photovoltaic solar energy throughout its analysis. The production profile of PV follows peaking natural gas generation; PV thus competes most directly with peaking natural gas plants. Additionally, solar PV and gas-fired peaking plants are also the closest competitors on a cost per-kilowatt hour basis.